Generally, a resistor is a passive electrical component that limits the flow of electrical current. A resistor may be constructed of various compounds and films with two or more wire leads to allow connection to a circuit. The ratio of the voltage applied across the resistor to the current flow through the resistor is called resistance. Resistance is measured in Ohm's.
Traditionally, the resistance of a resistor may be increased by increasing the size of the resistor itself. This increase in size of the resistor is opposed to the miniaturization of semiconductor dies. Therefore, the size of resistors of resistors has steadily decreased. However, the processing steps to manufacture miniaturized resistors may lead to a variation in the resistance.